The network of embedded tubes and pipes used in radiant heating can turn the radiant surface such as floors, walls and ceilings into cold surfaces that absorb sensible heat from surrounding sources. The radiant cooling together with forced-air cooling system offer more efficient way to meet building’s air quality requirements. The efficient property of hydronic radiant cooling to absorb sensitive loads in combination with forced-air that efficiently removes excess humidity (latent loads) can and will significantly reduce overall energy consumption of the building.
In order to prevent condensation on cooled floors, walls and ceilings the temperature of supply water should be 2°C (3°F) above anticipated dew point of the space. This precision control is not possible without sensors that monitor temperature and relative humidity of space air and hydronic fluid supply temperature. Such control accuracy is possible to achieve only with electronic control and floating action mixing. The use of wide-spread thermostatic mixing valves to control radiant heating supply temperature will be useless in radiant heating and cooling system.

-The Resol ALL-in-ONE  -DeltaSol MX - System controller -

has all of these functions on board!
The diagram below depicts generic system that combines hydronic radiant surface and forced-air cooling.

A2W Radiant Cooling Example
In the picture above, an AIR TO WATER (A2W) heat pump supplies hot and cold water that is stored in heating and/or cooling buffer tanks. The MX controller automatically switches between heating and cooling modes based on outdoor temperature and/or an input switch. Based on the system mode of operation, 3-way diverting valves manage buffer tanks loading and discharge. In the cooling operation mode, an air handling unit is fed straight from the cold buffer tank. The temperature of the cooling buffer tank follows the linear outdoor reset function. All radiant cooling circuits will maintain higher temperature with electronic supply temperature control by floating action mixing valve.
The key for controlling of hydronic cooling is an ability to maintain the temperature of radiant surface above the dew point to avoid condensation. The MX controller applies different logic (heating or cooling) to the same mixing valve and recognizes the call for heat or cooling from the same heating-only thermostat! The Resol FRH/FRHd sensor is used for measuring the relative Humidity and space air temperature.
RESOL MX controller modulates the mixing valve, keeping supply temperature 2°C (3°F) above, anticipated dew point it calculates.
For detailed control sequences and control programming, we welcome you to contact us.

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